show your steps.
3AB
+ C3D
_______
7BD
The following addition example, each letter represents one digit. It’s the same letters represent the same digit, and different letters represent different digits, what digit does A represent?
Step 1: Add the units column: B + D = D (since B + D = 10 + B + D - 10 = D)
Step 2: Add the tens column: 3 + C = D (since 3 + C = 10 + 3 + C - 10 = D)
Step 3: Add the hundreds column: 3 + A = 7 (since 3 + A = 7)
From step 3, we can determine that A = 4.
Therefore, A represents the digit 4.